Here at Loose Fill Blowers we have developed tools to allow loose fill insulation to be easily transferred into cavities and corners of the loft which are not easily insulated by any other means..

The tool utilises an industrial vacuum cleaner , which must have the facility to move the hose from the vacuum side of the machine , to the blowing side of the machine , and uses this air pressure to blow loose fill insulation along a pipe . All tests and experiments were done with a vacuum cleaner from Wickes..

The unit itself is light and easily hand held , if the insulation is needed in a wall cavity , it is simply held against ,or placed into , a hole in the wall ....there must be a corresponding hole somewhere to allow the air to escape , or the compartment simply becomes pressurized....typically gauze or mesh is arranged over this second hole to trap the insulation....
If the insulation is needed overhead in a restricted loft space for example , then extension pipes can be added , both on the vacuum cleaner blower pipe , and the output pipe blowing the insulation , but , as always with any fluid motion in a pipe , any extra length of pipe adds drag and thus back pressure to the arrangement which in turn affects the efficiency of the unit ....the best rule of thumb is to always use the shortest tube lengths possible...

The best tube to use is smooth bore plastic intended for plumbing drains...the unit utilises and/or is compatible with solvent weld plastic waste pipe.....where the 32mm labelled brands are actually 34mm outside diameter , and the 40mm version is actually 43mm O.D........The corrugated flexible pipes normally used for vacuum cleaners are not recommended on the output side as they trap the insulation and introduce a large amount of back pressure...

The unit itself is manufactured mostly from a cunning arrangement of readily available plastic pipe and fittings....and has a main air path which has the blown air introduced at one end , and the mixed air and insulation emerging at the other end . A side tube is introduced into the insulation which is sucked up into the airflow .
The 'down side' of this simple arangement is that the insulation has to be hand fed into the pickup tube in order to prevent blockages......

Vermiculite is the favorite material for loose fill insulation and by its very nature varies in size and shape of granules , and being just slightly squashy can easily form a blockage unless the material is guided into the pickup tube in an orderly manner . This may be considered a problem , but main users are DIY enthusiasts who do not really measure their time . The task can be done by unskilled labour ie. wives or girlfriends ......It can take an hour or two to feed a 100 litre bag of vermiculite into a normal ceiling ie. 8 foot overhead.......

Recycled and treated newspaper is the other main loose fill insulation available in the U.K. . and the degree to which blockages are prevented depends largely on how well the compressed paper 'fluff' is broken up into an even texture..

If trying to blow insulation into the corner of a loft or other confined space , it can be found neccessary for the user to lay down and use a smaller polythene bag to hold the insulation..(as opposed to a bucket or the original large bag in which the insulation arrives..)..in this situation there is a tendency for the vacuum effect to suck the polythene bag flat , and for this application there is a modification which feeds bleed air pressure into the bag.....

The techniques used in a typical installation are as follows....
In order to blow insulation overhead into a sealed narrow loft space under a flat roof , holes were cut in the ceiling plasterboard using a 70mm (2¾ inch) circular saw....

..and the discs saved to make good later....


....a plastic lid can be used to catch the dust....working at low speed by hand makes less mess....



..a wooden strip 200mmx68mm is introduced through the hole after a visual inspection for internal obstructions . The wooden strip has a hole 44mm (1¾ inch) in diameter cut in the middle of it .


The wood is arranged to lay flat inside the loft with the hole centred over the hole in the plasterboard.. ...screws up through the the plasterboard secure the wood in place...
The 44mm hole in the wood is a snug fit for 42mm plastic pipe itself or the couplings used to join 38mm pipe and a mixture of pipe work can be used to blow the first layers . With 38mm pipe the slightly larger diameter of the back-to-back couplings or the 90 degree bends seals quite well and prevents the insulation from falling back down through the gap..
The 90 degree bend allows the insulation to be blow sideways in the loft space and it can come to a rest up to a metre from the hole itself..
The pipe couplings can be held together with gaffer tape (duct tape) to allow re-arrangement at will.... as opposed to glueing them together permanently.....

After the level of insulation in the loft space has reached the point where significant quantities fall back out of the hole when the feed pipe is withdrawn ....


....a section of 42mm plastic pipe 100mm long (or as long as the cavity allows)..is glued into the hole in the wood using a hot melt glue gun....this 'chimney' allows a significant further quantity of insulation to be blown up into the loft using a smaller 38mm feed pipe which conveniently is a snug fit inside the 42mm one..


..When sufficient insulation is around this particular hole , a small quantity of the insulation in a plastic bag or cling film is used to block the 'chimney'.


.and the disc of plasterboard is glued and screwed back into place and the surface made good with filler and paint.

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..and so on to the next hole......multiple holes can be fed at once with multiple blower setups , bearing in mind the airflow , there has to be somewhere for the air to go to....

,,,small tv cameras from Mapin can be used to investigate the structure of confined spaces and also check on the progress of the insulation fill....as with any insulation installation you have to take care to maintain airflow to parts of the roof space which are intended to be ventilated in order to prevent the build up of condensation......
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